GHSA-m837-xvxr-vqwg: Flowise Hardcoded CORS Wildcard On TTS Vulnerability

MODERATE
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CWE-942
Published
Advisory Summary

GHSA-m837-xvxr-vqwg is a MODERATE hardcoded cors wildcard on tts vulnerability (CWE-942: Permissive Cross-domain Security Policy with Untrusted Domains) affecting Flowise libraries in the npm ecosystem. The issue involves hardcoded cors wildcard on tts endpoint enables cross-origin credential abuse from any webpage. Remediation is available by upgrading affected packages to version 3.1.2.

GHSA-m837-xvxr-vqwg at a Glance

CVE Identifier N/A
GHSA Identifier GHSA-m837-xvxr-vqwg
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-942: Permissive Cross-domain Security Policy with Untrusted Domains
Affected Product Flowise
Package Ecosystem npm
Published Date
Last Updated

How to Fix GHSA-m837-xvxr-vqwg

To remediate this vulnerability, upgrade all affected Flowise dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

flowise fixed: 3.1.2 
npm install flowise@3.1.2
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls flowise

How to Check if You Are Affected

To determine whether your Node.js application is affected by GHSA-m837-xvxr-vqwg, inspect your project dependencies using npm:

npm ls flowise

Analyze the terminal output to locate any version of Flowise in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.1.2), your application is affected.

Note: The npm ls flowise command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-942: Permissive Cross-domain Security Policy with Untrusted Domains, where the product uses a web-client protection mechanism such as a content security policy (csp) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate. In Flowise, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary The TTS generation endpoint sets `Access-Control-Allow-Origin: *` as a hardcoded response header, independent of the server's CORS configuration. This enables any webpage to make cross-origin requests to generate speech using stored credentials. ### Root Cause ```typescript // packages/server/src/controllers/text-to-speech/index.ts:83 res.setHeader('Access-Control-Allow-Origin', '*') res.setHeader('Access-Control-Allow-Headers', 'Cache-Control') ``` ### Impact - Cross-origin credential abuse — any webpage can trigger TTS using stored credentials - Bypasses the server's CORS policy (`getCorsOptions()`) which is otherwise restrictive by default - Combined with Finding 3 (TTS credential abuse), enables drive-by credential abuse via malicious webpages ### Suggested Fix Remove the hardcoded CORS wildcard and let the server's CORS middleware handle the headers: ```typescript // Remove these lines: // res.setHeader('Access-Control-Allow-Origin', '*') // res.setHeader('Access-Control-Allow-Headers', 'Cache-Control') ``` --- ## References - `packages/server/src/controllers/text-to-speech/index.ts` line 83

GHSA-m837-xvxr-vqwg Affected Flowise Versions

1 component(s)
Fixed Versions:
3.1.2
Product / Package Ecosystem Affected Versions Fixed Version
flowise
npm/flowise
npm
< 3.1.2
3.1.2

References

GitHub Advisory / Wiki ADVISORY
https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-m837-xvxr-vqwg
Flowise Source Repository REPOSITORY
https://github.com/FlowiseAI/Flowise

Frequently Asked Questions

What is GHSA-m837-xvxr-vqwg?
GHSA-m837-xvxr-vqwg is a security vulnerability in Flowise involving Hardcoded CORS wildcard on TTS endpoint enables cross-origin credential abuse from any webpage under CWE-942: Permissive Cross-domain Security Policy with Untrusted Domains.
Which Flowise versions are affected?
Affected versions include releases prior to 3.1.2 across affected packages: flowise.
What version fixes GHSA-m837-xvxr-vqwg?
Upgrading to 3.1.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is flowise affected?
Yes, flowise is affected in releases prior to 3.1.2. Upgrade your dependency to 3.1.2 or later.
What CWE is associated with GHSA-m837-xvxr-vqwg?
GHSA-m837-xvxr-vqwg is classified under CWE-942: Permissive Cross-domain Security Policy with Untrusted Domains (The product uses a web-client protection mechanism such as a Content Security Policy (CSP) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate.).
How can I check npm dependencies for GHSA-m837-xvxr-vqwg?
Run the dependency tree command: 'npm ls flowise'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-m837-xvxr-vqwg",
  "modified" : "2026-05-20T15:38:02Z",
  "published" : "2026-05-20T15:38:02Z",
  "aliases" : [ ],
  "summary" : "Flowise: Hardcoded CORS wildcard on TTS endpoint enables cross-origin credential abuse from any webpage",
  "details" : "### Summary\n\nThe TTS generation endpoint sets `Access-Control-Allow-Origin: *` as a hardcoded response header, independent of the server's CORS configuration. This enables any webpage to make cross-origin requests to generate speech using stored credentials.\n\n### Root Cause\n\n```typescript\n// packages/server/src/controllers/text-to-speech/index.ts:83\nres.setHeader('Access-Control-Allow-Origin', '*')\nres.setHeader('Access-Control-Allow-Headers', 'Cache-Control')\n```\n\n### Impact\n\n- Cross-origin credential abuse — any webpage can trigger TTS using stored credentials\n- Bypasses the server's CORS policy (`getCorsOptions()`) which is otherwise restrictive by default\n- Combined with Finding 3 (TTS credential abuse), enables drive-by credential abuse via malicious webpages\n\n### Suggested Fix\n\nRemove the hardcoded CORS wildcard and let the server's CORS middleware handle the headers:\n\n```typescript\n// Remove these lines:\n// res.setHeader('Access-Control-Allow-Origin', '*')\n// res.setHeader('Access-Control-Allow-Headers', 'Cache-Control')\n```\n\n---\n\n## References\n\n- `packages/server/src/controllers/text-to-speech/index.ts` line 83",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "flowise"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.1.2"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 3.1.1"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-m837-xvxr-vqwg"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/FlowiseAI/Flowise"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-942" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-20T15:38:02Z",
    "nvd_published_at" : null
  }
}